Copper Country pollinators — they come buzzing

Biological Bits

May 30, 2014

This column will stray from its mostly fishy nature, but will be of interest to wild berry pickers, hunters and anglers, as the production of wild fruit is important socially, economically and environmentally. Just ask the thimbleberry/blueberry pickers, jam makers and hunters. Just ask anglers also, as terrestrial insects are important fish food. One of my favorite dry fly patterns is the bee.

What are pollinators?

Pollinators are organisms (typically insects, but also some birds and small mammals) that visit flowers and collect pollen on their bodies. In the Copper Country, most of our pollinators are insects, not only the European honey bee that we are familiar with, but also hundreds of species of native bees, wasps, flies, butterflies, and moths.

Why are pollinators important?

As these insects move from flower to flower, they move pollen around, fertilizing other flowers as they go. Our native pollinators are essential to the production of the vast majority of our fruit, vegetable and nut crops and provide $2.4 billion in agricultural services every year. These insects also pollinate most of our wildflowers, shrubs and trees and are key players in maintaining biological diversity. Many wasp pollinators collect other insects to feed their young, providing this additional pest control benefit to agriculture. Several wasp and fly pollinators are parasites on other insects and their larvae, also providing invaluable control of pests.

Types of Pollinators

Bees - Prior to the arrival of the first European colonists in the 1600s there were no honey bees in North America. Pollination services were provided by more than 4,000 species of native bees, ranging in size from tiny sweat bees to yellow-faced bees, leafcutter bees, large bumble bees and carpenter bees. Most native bees are selective to the type of flower they visit, often specializing on a particular family or genus of plants. Native bees (except bumble bees) are solitary, meaning the females build and provision nests by themselves, with no division of labor between workers, queens, etc. Bumble bees are similar to honey bees. A single queen bee starts a nest or hive and lays unfertilized eggs that produce exact replicates. These identical offspring become workers that provision and guard the nest, but produce no offspring. Native bees build nests in places including old plant stems, dead trees, logs, rock crevices, old animal burrows and tunnels in sandy soils.

Wasps - Most wasps (roughly 12,000 species in North America) are pollinators. These include common colonial species like yellow jackets, paper wasps and many solitary species. While sometimes a nuisance at summer picnics, a hive of yellow jackets will pollinate thousands of flowers and destroy tens of thousands of caterpillars over one growing season! Paper wasp colonies also collect hundreds of caterpillars every year to feed their young. Mud daubers pollinate flowers and collect spiders to provision their nest, while sand digger wasps collect horse and deer flies to feed their young. Other solitary wasps collect flies, crickets, grasshoppers, and leaf hoppers. Although many wasps can sting, most are very docile and will sting only when their nests are threatened or if they are carelessly handled.

Flies - Flies are one of the largest groups of insects in North America with more than 20,000 species. They range in size from minute gnats and midges to the very large mydas flies measuring more than 25mm in length. While this group contains pests (like the mosquitos, deer flies, flesh flies and house flies), many others are predators or parasites of other insects as well as pollinators. Even mosquitos, which actually feed on nectar from flowers instead of blood, are pollinators for some flowers, especially certain orchids. Some flowers emit odors of rotting flesh or excrement to attract certain flies. Many mimic bees and wasps for protection from predators. Flies can always be told from bees or wasps by having only one pair flight wings. Flies lack stingers and most do not bite.

Butterflies and Moths - After bees, butterflies, skippers and moths are the most readily recognized pollinators. These insects comprise the order Lepioptera that has more than 11,500 species in North America. Moths outnumber butterflies and skippers by more than 10 to 1 as does the pollination services moths provide. Like the flies, the order Lepidoptera has pests such as the cabbage butterfly, meal moths, gypsy moth and spruce budworm. They provide millions of dollars in pollination services annually. Their larvae (caterpillars) feed on a variety of plants, shrubs and trees, with a few being agriculture and forestry pests. Most importantly, caterpillars provide food for other insects, birds, fish, amphibians, reptiles and other mammals.

Threats - The development and use of organophosphate insecticides in the 20th century greatly reduced pollinator populations worldwide. Landowners can minimize negative impacts and enhance their properties for pollinators by: Minimizing or eliminating the use of chemicals, deploying bee boxes or bee bundles that provide nesting sites, and allowing wasps and mud daubers to build nests and co-exist, to name a few.

The above are selected excerpts from an article commissioned by the Houghton Keweenaw Conservation District and written by James A. Bess. The complete article, with pictures, can be obtained from the HKCD at 711 W Lakeshore Drive, Houghton, or calling 906-482-0214.